[PATCH -mm 04/14] bootmem: add debugging framework

Johannes Weiner
2008-06-03T01:59:27Z

[-- Attachment #1: bootmem-debugging.patch --]
[-- Type: text/plain, Size: 3403 bytes --]

Introduce the bootmem_debug kernel parameter that enables very verbose
diagnostics regarding all range operations of bootmem as well as the
initialization and release of nodes.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
---

mm/bootmem.c | 51 ++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 44 insertions(+), 7 deletions(-)

--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -34,6 +34,22 @@ unsigned long saved_max_pfn;

bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;

+static int bootmem_debug;
+
+static int __init bootmem_debug_setup(char *buf)
+{
+ bootmem_debug = 1;
+ return 0;
+}
+early_param("bootmem_debug", bootmem_debug_setup);
+
+#define bdebug(fmt, args...) ({ \
+ if (unlikely(bootmem_debug)) \
+ printk(KERN_INFO \
+ "bootmem::%s " fmt, \
+ __FUNCTION__, ## args); \
+})
+
/*
* Given an initialised bdata, it returns the size of the boot bitmap
*/
@@ -104,6 +120,9 @@ static unsigned long __init init_bootmem
mapsize = get_mapsize(bdata);
memset(bdata->node_bootmem_map, 0xff, mapsize);

+ bdebug("nid=%d start=%lx map=%lx end=%lx mapsize=%ld\n",
+ bdata - bootmem_node_data, start, mapstart, end, mapsize);
+
return mapsize;
}

@@ -198,6 +217,8 @@ static unsigned long __init free_all_boo
count += i;
bdata->node_bootmem_map = NULL;

+ bdebug("nid=%d released=%ld\n", bdata - bootmem_node_data, count);
+
return count;
}

@@ -255,6 +276,10 @@ static void __init free_bootmem_core(boo
if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);

+ bdebug("nid=%d start=%lx end=%lx\n", bdata - bootmem_node_data,
+ sidx + PFN_DOWN(bdata->node_boot_start),
+ eidx + PFN_DOWN(bdata->node_boot_start));
+
for (i = sidx; i < eidx; i++) {
if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
BUG();
@@ -360,13 +385,16 @@ static void __init reserve_bootmem_core(
if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);

- for (i = sidx; i < eidx; i++) {
- if (test_and_set_bit(i, bdata->node_bootmem_map)) {
-#ifdef CONFIG_DEBUG_BOOTMEM
- printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);
-#endif
- }
- }
+ bdebug("nid=%d start=%lx end=%lx flags=%x\n",
+ bdata - bootmem_node_data,
+ sidx + PFN_DOWN(bdata->node_boot_start),
+ eidx + PFN_DOWN(bdata->node_boot_start),
+ flags);
+
+ for (i = sidx; i < eidx; i++)
+ if (test_and_set_bit(i, bdata->node_bootmem_map))
+ bdebug("hm, page %lx reserved twice.\n",
+ PFN_DOWN(bdata->node_boot_start) + i);
}

/**
@@ -454,6 +482,10 @@ alloc_bootmem_core(struct bootmem_data *
if (!bdata->node_bootmem_map)
return NULL;

+ bdebug("nid=%d size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
+ bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
+ align, goal, limit);
+
/* bdata->node_boot_start is supposed to be (12+6)bits alignment on x86_64 ? */
node_boot_start = bdata->node_boot_start;
node_bootmem_map = bdata->node_bootmem_map;
@@ -561,6 +593,11 @@ found:
ret = phys_to_virt(start * PAGE_SIZE + node_boot_start);
}

+ bdebug("nid=%d start=%lx end=%lx\n",
+ bdata - bootmem_node_data,
+ start + PFN_DOWN(bdata->node_boot_start),
+ start + areasize + PFN_DOWN(bdata->node_boot_start));
+
/*
* Reserve the area now:
*/

--